The present invention relates in general to a storage control system in which a second storage controller is connected to a first storage controller. More specifically, the invention relates to a storage control system and a storage control method in which storage resources of the second storage controller can be controlled, for example, the power supplied to driving mechanisms of the storage resources can be controlled and control access of a host apparatus to the storage resources can be controlled.
As such a storage controller, a disk array device is known. This disk array device has a plurality of disk drives arranged in an array shape and is constructed based on a RAID (Redundant Array of Independent Inexpensive Disks) configuration. On physical storage areas of the respective disk devices, logical volumes (logical devices) which serve as logical storage areas are provided. The host apparatus can perform read and write operations of desired data to the disk drives by issuing write and read commands having predetermined formats to the disk array device.
As principal uses of such a disk array device, conventionally, transactions or databases are known. For these uses, the disk array device needs to have high performance and reliability. For this reason, as an HDD to be mounted on a storage controller which is employed for these uses, an HDD (Hard Disk Drive) having high performance and reliability is adopted. In general, an HDD satisfying such a performance criteria is expensive, since highly reliable parts must be used.
In order to suppress the power consumption of the disk array device having such an HDD, a technique, in which control of the current simply to a spindle motor for driving the HDD is performed, is disclosed in Japanese Patent Laid-Open No. 2000-293314.
In the field of use of a storage controller, a concept of DLCM (Data Life Cycle Management) has been proposed. According to this concept, by paying attention to the fact that a data value changes over time, effective data storing management is performed. For example, the storage of data having little value into an expensive disk array device, which is designated as ‘the first tier’ is a waste of the storage resources. Thus, information having little value is archived by using an inexpensive disk array device, such as a HDD, which is designated as ‘the second tier’ and which has a reliability, responsiveness, and durability lower than that of the first tier. Among data to be archived, there is data which is obligatorily preserved for a constant period under certain laws or office rules. This is different according to the type of data or the like. The kind of data should be preserved for a period of several years to tens of years (if necessary, beyond that period).
Japanese Patent Laid-Open No. 2000-293314 describes a system in which a second storage controller is connected to a first storage controller and stored data in the first storage controller is archived in the second storage controller. However, this configuration is used to control the power consumption with respect to the first storage controller and is not intended to control the power consumption with respect to other storage controllers connected to the first storage controller.